Engine Classification
Financial or legal field · Modification blocked by policy
Reason: KSeF rejects invoices with issue dates more than 30 days before submission. The invoice date cannot be changed retroactively. Issue a new invoice with a current date, or submit through alternative channels if KSeF deadline has passed.
What is KSEF-002?
KSEF-002 is a fatal validation rule defined in the KSeF specification (POL national rules).
When this rule fires, the invoice is rejected by Peppol access points and never reaches the buyer.
Why This Error Matters
KSEF-002 is a hard failure — the invoice must be corrected and re-sent before it can reach the recipient.
Validator Behavior
- ·Causes invoice rejection
- ·Error returned: KSEF-002
- ·Specification: KSeF
How to Fix It
Technical Reference
Common Causes
- ·Invoice created but not submitted in time
- ·Backlog of invoices
- ·System date misconfiguration
Seeing this in production? The API handles KSEF-002 automatically. See the fix response →
Frequently Asked Questions
Invoice issue date cannot be more than 30 days before KSeF submission date. Older invoices will be rejected by the system.
Submit invoices within the 30-day window. This error involves a protected field — Invoice Navigator flags it in your pipeline so your team can correct it at the source.
Yes, KSEF-002 is a critical error that will cause invoice rejection. It must be fixed before submission to ensure your invoice is accepted by the recipient's system.
KSEF-002 involves a financial or legal field that cannot be auto-modified by policy. Invoice Navigator detects and flags this error immediately, but the correction must be made manually in your ERP or invoicing software.
Related Content
Last updated: 3 March 2026
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This error involves a financial field that can't be auto-modified. We'll flag it with a clear diagnosis so you can fix it at the source.